So-called bitcoin mining is different from what is perceived in daily life. It is a reward behavior in blockchain networks. Blockchain is a database, where everyone can participate in data processing. But without team maintenance, it is difficult to maintain data for free for users participating in blockchain network governance. Bitcoin is the reward rule under this data maintenance.

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At a certain time, whoever processes the data the fastest and best, and is recognized by the system, will receive the reward, that is, the corresponding amount of bitcoin. Because the number of bitcoins is limited, and the behavior of obtaining bitcoins is actually similar to gold mining, the method of acquiring bitcoins is called mining. Those involved in data processing are called miners, and the machines used to participate in data maintenance are called mining machines.
To make it more easy to understood, it is like a group of players hitting one boss simultaneously in a game. The one who has the most output and who kills the boss first will get the rewards given by the system.